Synthesis and mechanical properties of large size silica shell microcapsules for self-healing cementitious materials

Abstract

Synthesis of inorganic shell microcapsules is very challenging in the field of self-healing cementitious materials. Here, we report successful fabrication of epoxy resins encapsulated into silica shell microcapsules with average particle size greater than 100 μm via interfacial polymerization. The silica shell microcapsules show good thermal stability. The nanoindentation test was used to determine the micromechanical properties of the microcapsules. The results show that silica shell microcapsules exhibit brittle rupture, high Young’s modulus and hardness of the shell, with a better deformation resistance. The observed micromechanical properties are attributed to the regular tetrahedral crystal structure of the silica shell materials.